In modern farming, hay and straw is often harvested in large bales, which may be square or rectangular in section. These are typically left in place on the field after the baling operation and are often stacked two or more high. Typically, the stacked array of bales left on the field, or in a storage yard, be retrieved periodically, as required, and delivered to a cattle feeding station or the like. At the delivery end, the bales are then either chopped or separated to distribute the hay or straw to cattle or other livestock for feed or bedding. It is preferable that the entire operation be carried out with a single piece of equipment which picks up the bales from the field, places the bales on a towable flatbed trailer or the like for transport, and separates or chops the bales at the delivery point and discharges the hay or straw with sufficient force to emplace a suitable bed at a point remote from the device. Conveniently, such an apparatus is operable by a single operator, and is desirably readily towed behind and powered by a conventional tractor.
Conventionally, farmers transfer large hay bales from the field onto a flatbed trailer by means of a fork lift. A conventional fork lift, whether integrated into a tractor or otherwise, is not well suited for handling of stacked large bales, which may be stacked too high for a fork lift to safely and easily handle. In order to address this and other drawbacks of operating a separate lift, a forklift-type hoist may be integrated into a towable flatbed trailer or bale processor: Examples of an integrated fork lift/flatbed trailer arrangement are disclosed in patent numbers:
U.S. Pat. No. 5,090,630 (Kopecky et al.) PA0 Soviet Union 1704694 A1 (Lith Agic Acad) PA0 U.S. Pat. No. 4,597,703 (Bartolini) PA0 U.S. Pat. No. 4,449,672 (Morlock et al.)
It has been proposed to provide a combination fork/trailer combination which is uniquely suited for handling stacked bale arrangements. For example, U.S. Pat. No. 5,211,345 (Siebenga) discloses a trailer undercarriage, which supports a long deck hinged to the rear end of the undercarriage. A bale processing means such as bale chopper is mounted at the front of the undercarriage. The deck is tiltable on the undercarriage by means of fluid driven rams, between a generally vertical position and a horizontal position. An array of prongs or forks extends from an end of the deck. When the deck is tilted into a substantially vertical position, the forks point rearwardly. The trailer in this position may be backed into a stacked array of bales, whereby the forks engage the base of the stack of bales. The deck when thus oriented must be longer than the height of the bale stack being loaded. As the deck is tilted downwardly, the forks lift and tilt the bale stack rearwardly towards the deck. The stack is brought to bear on the deck as the same reaches its horizontal position. When the trailer is towed to a feeding station or the like, the bales may transferred from the tiltable deck to the processor, by tilting the deck forwardly to permit the bales to slide onto the processor. A drop between the deck and the processor causes the bales to tumble by one turn (90.degree.) as they drop from the deck of the trailer bed onto the processor deck, to expose a selected face of a bale to the processing means. The bales may then be chopped by means of the integral bale processor.
The above prior art arrangement suffers several potential drawbacks. First, the means by which bales are conveyed along the tiltable deck to transfer the bales from the deck onto the processor, relying on gravity to slide the bales along the deck, renders this aspect unreliable. It is desirable to provide a reliable, positive means to convey the bales along the deck into the processor. Second, it is not always desirable to cause the bales to tumble as they drop onto the processor deck. In some circumstances, the farmer may wish to directly transfer the bales onto the processor deck, in the same orientation as they rest on the tiltable deck. It is thus desirable to provide an arrangement whereby a farmer may select whether or not to tumble the bales in the transfer step. Further, there is no means provided in the prior art to prevent a stacked array of bales from toppling backwards, as the fork lift arrangement backs into the stack and engages the stack onto the tiltable deck. It is thus desirable to provide a means to temporarily fasten the bales to the deck as the same is tilted away from the vertical. Rearward toppling of the stack can be inconvenient, as it renders pickup of the bales difficult and may cause the bales to break; it is also dangerous, since the bales could injure a worker when they topple.
It is also desirable to provide a component of the bale handling apparatus for cutting the baling twine or wire as the bales are transferred onto the tiltable deck. The cutting operation should be performed in the same operation as the transfer of the bales from the field stack onto the trailer deck. This is a useful function in light of the tendency of baling twine on the lowermost bale to tangle as the bale shifts relative to the ground during the transfer. Finally, the bale processors of the prior art appear to be suitable only for grinding or chopping of bales. It is desirable to provide a means for separating rather than chopping of bales, in order to preserve relatively long lengths of straw, in an arrangement of the type characterized above.